To get an idea of the extent of use of this paradigm, I use several key strings in Google. The variety of the results is extensive, and examples are from a diversity of regional uses on several continents, though some antipodean glossaries claim it be Australian slang.

one/two/... X short of a Y

Google search strings: "short of a" / "short of an" / "shy of a" / "shy of an"

Selection of results for short:

"one tinny short of a six-pack", "one sausage short of a barbicue", "one egg short of an omelette", "one slice short of a loaf", "one banana short of a bunch", "one brick short of a full load"

"two sandwiches short of a lunchbox", "two biscuits short of a picnic", "two cards short of a deck", "two figs short of an oasis", "two chops short of a barbie"

"a few tacos short of a combo platter", "a few cards short of a full deck", "a few fries short of a happy meal", "a few kernels short of a cob"